ES2610705T3 - Damping device - Google Patents

Abstract

Damping device (10; 20; 30; 300; 310; 40; 50; 60; 111) comprising a first support element (11; 31; 41; 51; 61; 1111) and a series of slender metal structures (12 , 12 ', 12 ", 12n; 32, 32', 32", 32n, 33; 42, 42 ', 42 ", 42n; 52, 52'; 1112, 1112 ', 1112n, 1113, 1113', 1113n) having a first end and a second end, said slender metal structures respectively having a slenderness ratio equal to or greater than 10, in which the slender metal structures are respectively fixed at their first ends to said first support element, in which The slender metal structures are fixed at different points of said support element, characterized in that: - the mutual distance between the slender metal structures of at least one pair of slender metal structures (12, 12 '; 32, 33; 42 , 42 '; 52; 52', 62, 62 '; 1112, 1113) is equal to or less than 0.75 times its length -L-, said distance being measured with respect to their first extremes, - at least 90% of the planes perpendicular to the adjacent slender structures are mutually parallel or form an angle equal to or less than 20 °, - the slender metal structures are flat or sheet metal elements and / or Straight filiform or wire elements, and because the slender metal structures are arranged so that they absorb energy from the impacts that act in a direction perpendicular to the planes that in turn are perpendicular to the slender structures.

Description

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DESCRIPTION

Damping device

The present invention relates to improved damping devices and systems and / or components using said damping devices. The term "device" must be interpreted in its broadest meaning and encompasses finite and independent devices and damping systems, as well as parts or sub-assemblies incorporated into larger or more complex systems.

In a variety of applications, improved damping devices are required, referring to improvements to the ability to withstand a series of impacts from external sources, that is, durability, as well as a more efficient mechanism for energy dissipation, that is, a Enhanced protection

The fields of application of the damping devices are very different and vary from mechanical subsets such as bumpers for the automotive industries (cars, trucks) and bumpers on train platforms, to components intended to be incorporated into textile products for garments safety or fabrics such as jackets for motorcyclists. Even though, depending on the specific application or the field of use, both the duration and the improvement of the protection can provide a predominant advantage, the damping device according to the present invention is characterized both by its great durability and by an improvement in the protection.

In the field of closing systems, both characteristics are simultaneously important, for example, for the application of buffer stops for doors, windows and gates.

Patent DE 10 2012 204 059 B3, which is considered as the closest prior art, discloses a damping structure with slender metal structures.

Another remarkable aspect of the present invention is that its structural characteristics can be easily adapted to systems and components that have a very different size, whereby the damping device can be easily integrated into the final systems or components for different applications.

In a first aspect thereof, the invention relates to a damping device comprising a first support element, a series of slender metal structures that have a slenderness ratio equal to or greater than 10, in which the slender metal structure is respectively fixed by a first end thereof to said first support element, characterized in that:

• the slender metal structures are fixed respectively to different points of said first support element;

• the mutual distance between the slender metal structures of at least one pair of slender metal structures is equal to or less than 0.75 times their length -L-, that is, 0.75 x L, said distance being measured with regarding its first extremes;

• at least 90% of the planes perpendicular to the adjacent slender elements are mutually parallel or form an angle less than 20 °.

- the slender metal structures are flat sheet or sheet metal elements, and / or straight filiform or wire elements,

- the slender metal structures are arranged in such a way that they absorb the energy of the impacts that act in a direction perpendicular to the planes which, in turn, are perpendicular to the slender structures.

The invention will also be shown with reference to the following figures in which:

- Figures 1A and 1B show, in schematic form, a top view and a front view of a damping device according to the present invention comprising slender, laminar or sheet elements,

- Figures 2A and 2B show, in schematic form, a top view and a front view of an alternative embodiment of a damping device according to the present invention comprising slender laminar elements,

- Figures 3A to 3C show, in schematic form, a top view and alternative front views of a damping device according to the present invention comprising slender filiform elements,

- Figures 4, 4A and 5 show an alternative embodiment of a damping device according to the present invention comprising slender filiform elements,

- Figure 6 is a cross-sectional view showing an alternative embodiment of a damping device according to the present invention having a spherical geometric shape,

- Figure 7 is a partially broken away view showing a part of a damping device according to the present invention,

- Figure 8 is a photograph of damping devices according to the present invention,

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- Figure 9 is a photograph of a damping device manufactured according to the prior art,

- Figure 10 is a graph showing a comparison between the behavior of one of the devices shown in Figure 9 and the device of Figure 10,

- Figure 11 is an exemplary operating scheme of a system comprising a damping device according to the present invention.

In order to make the figures easier to understand, the dimensions and dimensional proportions of the elements have been altered in some cases, with particular but not exclusive reference to the height and width of the slender metal structures.

The slender metal structures suitable for use in the damping device according to the present invention, have a proportion of slenderness, that is, the proportion between its length -L- and the transverse dimension smaller -w-, equal to or greater than 10. Such As shown in the drawings, the slender metal structures of the invention are flat or sheet metal elements and / or straight filiform or wire elements. The embodiments of the invention shown in Figures 1 to 8 comprise both flat sheet and sheet metal elements, or straight filiform or wire elements, as will be described in detail below. The damping devices of the invention may also comprise combinations of flat or sheet metal elements and straight filiform or wire elements.

For clarity, the slender structures according to the present invention are straight or rectilinear (filiform) or flat or rectilinear (laminar), that is, at least 90% of the length of their tangential lines form an angle less than 5 ° with the axis (straight) or with the central (laminar) plane of the slender structure. The condition of 90% of the length takes into account that the slender structures are real and not ideal elements, and also that the ends of the slender structures may be distorted or deformed as a result of their placement in the damping device of the present invention. Similarly, the condition that the angle between the tangent lines and the slender structures is less than 5 ° takes into account the deviation from the ideal condition in which these elements are perfectly straight or flat.

Also, even though the preferred solution provides elements manufactured all of them by means of straight slender structures, it is possible that some of them (less than 10%) have a non-linear shape according to the previous definition. Said fraction is preferably less than 5% or even more preferably less than 1%.

These considerations are due, and take into account, that the damping system according to the present invention may comprise in some specific embodiments, a high number of slender straight or laminar structures, so that it is possible that some of them depart from the condition of ideal linearity as a result of assembly within the system, but without compromising or significantly affecting the overall behavior of the system.

As a clarification of the above, the slender elements in the damping system of the present invention are characteristic elements that collaboratively achieve the technical effect of improved damping characteristics, differently from the case of the cables of multiple filaments that will be commented below when referring to the state of the art.

The overall configuration of the damping devices according to the present invention is such that straight and / or flat slender structures resist compression loads directed along their axes in the case of filiform or wire elements, or parallel to their planes in the case of sheet or sheet elements.

Therefore, the damping devices of the present invention effectively take advantage of the so-called "buckling effect" of straight or flat slender structures, that is, their capacity under a compression and impact load, to have a transition from a simple compression to a folded, with the consequent great deformation.

In mechanical technique, buckling is a phenomenon due to lack of stability, which leads to a failure mode. Buckling defines a point where an equilibrium configuration becomes unstable under a parametric load change and manifests itself in various phenomena. Theoretically, buckling is caused by a fork in the solution to the static equilibrium equations. In a certain phase, under an increasing load, an additional load can be maintained in one of two equilibrium states. In the specific case of a straight structure subjected to a compression load, theoretically the equilibrium could be found in a simple compression or in a lateral deformation situation. Actually, the second situation is by far the most likely and involves large deformations.

If the slender structures are made of a material capable of withstanding large deformations, the energy absorbed increases radically. The present invention is based on an original scheme of slender structures suitable to take advantage of this physical effect to its fullest extent, so that they can be used in damping assemblies and devices.

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In view of the foregoing explanation and the embodiments depicted, it is also important to note that the slender structures used in the damping devices of the present invention are individual straight filiform elements and / or a flat laminar element that may be adjacent to each other, but not They are intertwined, neither united or twisted together.

Therefore, slender structures such as ropes or multi-strand cables are explicitly outside the scope of the present invention, because they cannot withstand any compression load, nor can they experience buckling. These types of structures are described in International Patent Publication WO 2013/042152 and in U.S.A. 3360225 and are based on the specificity and strength of cable structures consisting of a series of filaments or wires used as an active element for shock absorption or damping. It should be stressed that in this case the damping is achieved thanks to the friction between the adjacent wires and not by deformations resulting from displacements, as is the case according to the present invention.

As already noted, the present invention is based on the use of straight and / or flat structures that undergo buckling during use. The damping devices of the prior art are based, instead, on non-straight or flat structures such as those described in European Patent Application 2639476, U.S. Patent Application. 2009/0126288 and U.S. Patent Application 2011/0031665 that clearly cannot experience buckling deformations.

To further appreciate the difference between the damping devices of the prior art and those of the present invention, a comparative example in which a damping device of the prior art (see Figure 9) resembling the device has been used is shown below. shock absorber disclosed in European patent application 2639476.

In the present invention, straight and / or flat slender structures are arranged in such a way that they absorb energy from impacts acting in a direction perpendicular to planes that, in turn, are perpendicular to slender structures, for example, in the case of slender straight filiform structures, the impact forces that are essentially directed along their axes.

Slender structures in the form of flat sheet or sheet metal elements are preferred when a preferential crushing direction is needed, for example, in the case of headrests in vehicle seats, configured to prevent lateral movements and displacements as a result of an accident.

Slender structures in the form of straight filiform elements having a proportion equal to or greater than 10 between -L- and any transverse dimension are preferred in case of soft support elements, for example in fabrics incorporating metal wires.

The filiform elements can be tubular (i.e. their core is hollow) or in the form of wires.

Buffers that use slender metal structures are disclosed, for example, in U.S. Pat. 6530564 in which thin, filiform metal elements in the form of wires have common contact points with the support element. This configuration results in cushioning systems of a worse behavior compared to those manufactured according to the present invention, since the former only rely on deformation by folding, rather than by buckling.

International patent application WO 2010/053602 describes a different type of absorption structure for vibration damping, in which separate pillars of superelastic materials are disclosed as vibration absorption devices for MEMS (Electromechanical Microsystems) .

A schematic representation of a top view of a damping device 10 according to the present invention is shown in Figure 1A, while a front view of it is shown in Figure 1B.

In this embodiment, the slender structures -12-, -12'-, -12 "-, ..., -12n- are laminar elements all parallel to each other and fixed respectively at a first end thereof to a first element of support -11- that forms the base of the damping device -10-. According to the invention, the mutual distance of the slender elements of at least one pair of slender elements, for example the elements -12-, -12'-, is equal to or less than 0.75 x L, where - L- indicates the length of the slender metal elements measured with respect to their first ends.

The damping device 10 may also comprise a second support element connected to the slender metal structures at the second ends thereof, opposite their first ends. Figures 2A and 2B respectively show a top view and a front view of the damping device -20- according to the invention which, similar to the damping device -10- of Figures 1A and 1B, comprises a support base element and a series of parallel slender metal structures fixed thereto. The damping device -20- also comprises a second support element -23- connected to the second ends of the slender metal structures. As shown in Figure 2A, the second support element -23- can

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be fixed to the slender metal structures only partially, although the two support elements are preferably sized so that they overlap each other.

An interesting alternative configuration for both embodiments provides for the use of slender structures parallel and separated almost equally, provided that their mutual distance is equal to or less than 0.75 x L.

It is important to note that the structures shown schematically in the figures are theoretical structures. In a real damping device, in fact, the slender metal structures may not be perfectly parallel to each other. According to the invention, the planes perpendicular to the slender metal structures can also form an angle equal to or less than 20 ° without affecting the behavior of the damping device. In addition, the previous condition must be fulfilled, at least, for 90% of the slender metal structures, being acceptable that a small amount of them does not conform to the previous situation.

In the top view of Figure 3A a different embodiment -30- of a damping device according to the present invention is shown schematically, using filiform slender metal structures. According to this embodiment of the invention, the damping device comprises two different types of filiform slender metal structures. The differences between the slender metal structures can affect their shape, for example, the cross section, the diameter and the like, the metal material or both. In this case, a series of slender metal structures -32-, -32'-, 32 ”-, -32 '' '-, ..., -32n- are fixed on the first support element -31- , for example, a circular cross section, while a slender metal structure -33- of a different type having, for example a square cross section, is arranged in the central part of the damping device -30-. The condition according to which at least two slender structures are arranged at a mutual distance equal to or less than 0.75 x L, can be ensured by any of the pairs formed by the slender metal structure -33- and any of its adjacent slender metal structures -32-, -32'-, -32 ”-, -32 '' '-, ..., -32n-.

A first variant of the damping device -30- is a damping device -300- whose front view is shown in Figure 3B. The damping device -300- comprises a second support element -303- which acts as the upper support element.

Another variant of the damping device -30- is a damping device -310- whose front view is shown in Figure 3C. In this case, the slender metal structures have different heights, the ones arranged in the central part of the device being higher than those arranged progressively towards the periphery. The damping device -310- further comprises a second support element -313- fixed at the free ends of the slender metal structures and which is shaped like a dome.

Also, in this case, most, in particular 90% or more of the filiform metal elements are substantially parallel to each other, that is, they are filiform elements in a three-dimensional space, which means that their normal planes are parallel or form a angle equal to or less than 20 °.

It is important to note that the dimensions and dimensional proportions of the elements and structures shown in Figures 3B and 3C have been altered for the sake of clarity, and that the filiform slender metal structures have a maximum achura that is 1/10 or less than the height of the filiform metal structure.

The damping devices according to the present invention do not require a specific support element as regards the shape or structure. For example, Figure 4 schematically shows a top view of a part of a damping device -40- comprising a base support element in the form of an elongated band -41- on which the slender metal structures are fixed and aligned -42-, -42'-, -42 ”-, ... -42n- in a row. In the specific embodiment represented in Figure 4 all slender metal structures are equal to each other and separated by an equal, but as already described, this is not a requirement for the invention. Figure 4A shows a schematic front view of a part of the damping device -40-. The system -40- has been represented with only one base or a lower support element -41-, but it can also comprise an upper support element.

In other words, the main function of the support element is precisely to fix and support the slender metal structures and ensure that the geometric conditions in the planes perpendicular to the slender metal structure are satisfied.

As shown in the front view of Figure 5, the support element -51- of a damping device -50- according to the invention may not even be flat. Furthermore, as already indicated, it is acceptable that a percentage less than 10% of adjacent slender metal structures do not respect the geometric condition that their normal planes are mutually parallel or form an angle equal to or less than 20 °, such as , for example, in the case of adjacent slender metal structures -52-, -52'- shown in Figure 5, due to the non-planar shape of the support element -51 -.

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Figure 6 schematically shows a cross section of another embodiment of a damping device -60- according to the present invention. In this case, the damping device has a spherical geometric shape, in which the slender metal structures -62-, -62 ’-, ..., -62n- are fixed in a central support element -61-. The damping device -60- shown in Figure 6 can also comprise an outer support element -63- connected to the opposite ends of the slender metal structures -62-, -62 '-, ..., -62n-. Due to the spherical geometric shape of the damping device -60-, the slender metal elements cannot be parallel and in this case, at least 90% of them satisfy the condition that the planes perpendicular to the adjacent slender metal structures form angles equal or less than 20 °.

A possible way of fixing the slender metal structure to the support element is shown in Figure 7, which represents a partially broken view of a damping device 70 according to the present invention. As shown in the figure, the slender metal structures -72-, -72’- are inserted into a support element -71- in a certain part of their length.

In this case, two main possibilities are provided for fixing the slender metal structures. In one case, the support element -71- comprises cavities that are larger than the slender metal structures introduced into them. A filler glue fills the cavities thereby achieving a retention function. This solution is preferred in the case of rigid or hard support elements, which act as bases or substrates. In case of softer materials, such as fabrics, the slenderness of the structures allows them to fit into the support element.

In both cases, the terminal part of the slender structure penetrates the support structure, at least preferably up to 10% of said slender metal structure -L-.

Another possibility of fixing the slender metal structures in the support element is by means of slender structures embedded in a suitable filling that adheres to the support element and keeps the slender metal structures in position. In this case, the arrangement of a pair of support elements fixed to the opposite ends of the slender metal structures is preferred, because they contribute to retaining the filling.

In the case of soft support elements, the slender metal structures can be embedded in them, for example by sewing from a continuous metal wire, that is, a filiform metal slender structure, the sewing operation having the result of metal structures slender that satisfy the geometric constraints and the conditions of the present invention. A non-limiting example of an application for this type of damping device is in the manufacture of reinforced car seat belts.

As previously mentioned, all damping devices according to the present invention are characterized in that the mutual distance between at least two slender metal structures is equal to or less than 0.75 x L, where -L- is the length of the slender metal structure. Said distance is preferably less than 0.25 x L.

Another alternative definition of a preferred subclass of damping devices according to the present invention is by the density of slender metal structures per unit area, defined as the ratio between the surface occupied by the slender metal structures and the overall surface area of the support element of the damping device to which the slender metal structures are fixed. This ratio should be equal to or greater than 10-4, preferably equal to or greater than 10-3.

Suitable materials for the manufacture of the support element or elements may be metals, plastic, fabrics or polymeric materials. The thickness of the support element or elements is preferably equal to or greater than the diameter of the slender metal structures when filiform structures are used, or their thickness when using sheet or sheet structures, and more preferably equal to or greater than five times the diameter. or the thickness As a general rule, the harder the material from which the support element or elements is manufactured, the smaller its thickness. It will be understood that the tissues that incorporate the slender metal structures are not subject to these criteria.

The support elements of the damping device according to the invention can be made of the same or of different materials and can have the same geometric shapes, or other different geometric shapes.

Metal materials particularly suitable for use in slender metal structures are steels, preferably harmonic steel, aluminum and its alloys, copper and its alloys, titanium and its alloys, magnesium and its alloys, nickel and its alloys.

Particularly useful for the manufacture of straight and / or flat slender metal structures of the damping devices of the present invention is the use of intelligent metals. Smart metals comprise superelastic alloys and shape memory metals, the latter being known in the art with the acronym "SMA". These materials are widely known in the art and are described, for example in European Patent EP0226826 which refers to superelastic alloys and with Ni-Ti shape memory.

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Although various compositions of intelligent metals (SMA and superelastic) are known, the most commonly used intelligent metals are those based on Ni-Ti alloys, in which nickel and titanium constitute at least 70% of the alloy. The most common alloy contains 54 to 55.5% by weight of nickel and the rest of titanium (traces of other components are possible, its content usually being less than 1% by weight).

These alloys are fully fully characterized in a usual way not only by their composition, but also by their behavior when they are subjected to a heating process (usually providing them with a controlled current), which causes their transition between the two stable phases (Austenite, Martensite) . In particular, -As- and -Af- are the initial and final temperature at which the transformation of the austenitic phase begins, and on the contrary -Ms- and -Mf- are those that characterize the martensitic phase; More details and more information on the behavior of alloys undergoing reversible austenitic-martensitic transformations such as Nitinol can be found in various publications, such as in U.S.A. 4,067,752.

Other useful alloys also prevent the addition of quantities of one or more other elements. In this regard, other alloys appreciated in the art are Ni-Ti-Cu alloys, such as the alloys described in U.S. Pat. 4144057, or other ternary Nitinol alloys containing up to 10% of an additional element, such as those described in international patent application WO 2011/053737, in this regard Ti-Ni-Co and alloy alloys are particularly preferred Ti-Ni-Cr. The useful property of the sMa materials is that they return to their original form when they are subjected to a heating treatment, so that in the damping device according to the present invention they can have two main forms of use; they can recover the properties of the damping device after it has been subjected to too many impacts or to an excessive load, or they can be used as testimony when used in conjunction with other materials that have a higher elasticity, such as superelastic ones.

In view of the foregoing, there are certain preferred embodiments for the buffer device according to the present invention.

A first preferred configuration provides for the use of at least 30%, and more preferably at least 90% of the slender metal structures made of a superelastic metal material. These damping devices have the highest resistance.

Another preferred configuration of the damping devices according to the present invention provides for the presence of at least one slender metal structure with shape memory. This is particularly advantageous in the case of damping devices comprising a large number of slender supersrelastic structures, since the shape memory element may be the only testimony that the system has suffered an impact. The heating of the damping device can recover the shape of the filament with shape memory, thereby restoring its functionality as an impact sensor within the system.

Also, the damping devices that use a mixture of straight and / or flat slender structures made of different intelligent materials are advantageous, in particular damping devices comprising at least 30% of super-elastic slender structures and 30% of slender structures with memory of shape, or damping devices in which most of the slender metal structures are made of shape memory materials.

The property of restoring the shape of the slender metal structure made of shape memory metals can be used in two different ways. On the one hand, the functionality of a damping device can be recovered by means of a controlled heating (for example by providing an electric current to the slender metal elements) thereby causing a deformed shape memory element to return to its original form. On the other hand, it is possible to refine the properties of the damping device by controlling its temperature, for example, by choosing a slender metal structure that exhibits a shape memory behavior instead of a super-elastic behavior according to the specific situations, uses or applications.

As already noted, the preferred way to control the properties of slender structures with shape memory is by heating by means of the supply of an electric current. The power supply to the damping device can be advantageously arranged with a feedback control, usually in the resistance of the SMA wire.

The damping device according to the present invention can also be used not only to protect the devices in which it is installed, but also the elements that interact with it. More specifically, it can be part of urban elements such as traffic lights, protection profiles on highways, safety systems on racetracks, in order to provide improved safety conditions in case of accidents.

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An example of this structure and this concept, using a damping device comprising slender structures controlled with shape memory, is shown schematically in the top view of Figure 11. In this case, a system -110- includes a damping device -111- which contains a support element -1111- that acts as a base on which they are fixed on a series of slender metal structures. In the specific example shown in Figure 11, the damping device comprises two different types of slender metal structures indicated respectively by reference numerals -1112-, -1112 '-, ..., -1112n- and -1113-, - 1113'-, -1113n-. The slender metal structures -1113-, -1113’-, -1113n- are made of a shape memory metal. It should be noted that Figure 11 is a simplified scheme, and that said element -111- may be more complex, or be the most important part (for the purpose of the present invention) of a larger device. The damping device -111- is connected to a -112- controller (not shown) that can supply a current -I-. The intensity of the current can be regulated according to one or more external inputs that can be of a different type and nature. In the specific example shown in Figure 11, there are three different types of sensors, a reconstructive scenario -113- (for example, a digital camera), a pressure-impact sensor -114, and a manually-operated input -115- . More or less elements may be present and also their nature may be different, as already highlighted in the scheme of Figure 11, which is only an example of them.

Among other useful applications are extenders for people with injuries, safety clothing, safety belts, shock absorbers for home and industry, accessories for cyclists, bumpers, bumpers for closing systems, parts of packaging of items or of fragile equipment.

Safety belts are not the only possible placement or use inside vehicles and transport systems in which the damping devices according to the present invention provide additional advantages, for example they can be incorporated in elements such as side doors, seats, and the like in order to increase safety in case of accidents.

Also, the damping device according to the present invention can be installed in support systems or in devices such as bearings.

The damping devices according to the present invention may be part of another system and therefore may have additional elements or layers in contact with their support element or elements. In addition, in the final systems, there may be more than one damping device according to the present invention, for example, as a sequence of overlapping systems in which the first support structure of a system is the second support structure of the following system. In this case, it may be particularly advantageous to couple systems with different impact resistance, providing a type of damping compound device with increased layer protection.

The invention will be further described by means of the following non-limiting examples.

Example 1

A series of damping devices according to the present invention have been prepared. All these systems have common geometric characteristics as shown in Figure 8. These devices are manufactured with two parallel metal support elements in the form of 70 x 18 mm aluminum plates of a thickness of 10 mm, these plates being separated by middle of 39 slender metal structures arranged in three parallel rows. These elements are essentially parallel to each other and the minimum distance between them is 5 mm.

The slender metal structures are in the form of circular wires with a diameter of 0.5 mm and a length of 30 mm, 5 mm being the length of the slender elements that penetrates the upper and lower support elements that, therefore, are 20 mm apart. The support elements have holes of 0.6 mm in diameter to accommodate the slender metal structures; A cyanoacrylate adhesive was used to fix and retain the slender metal wires in the perforated support structure.

Four different samples of damping devices were manufactured using a different metal for the slender structure, in particular:

Sample 1 (S1): galvanized steel wires Sample 2 (S2): harmonic steel wires

Sample 3 (S3): Nitinol wires with shape memory (for .90 ° C)

Sample 4 (S4): superelastic Nitinol wires (for .25 ° C)

The damping devices were tested in impact tests with a pendulum to check the energy absorbed in the impact as well as the resistance of the devices samples 1, 2, 4 were subjected to multiple impacts with the same energy (5 strokes) increase the energy, starting from 0.325 J to 2.925 J in steps of 0.325 J. Only sample 4 was also tested at 11.7 Joule.

Amsler, which allows shock absorbers. The and then

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Sample 3 that comprised wires with memory in an experimental way was a sort of accelerated test and was subjected to 2 impacts for each energy level, since after each impact on the Amsler machine it was subjected to a thermal treatment to recover the original shape of the wire and slender structures.

The tests for the various samples stopped when the damping device lost its structural integrity, that is, there was a significant variation in the distance of the support element, and / or most metal wires lost their straight configuration; in the case of sample 3, this corresponds to the fact that the wires did not recover their shape, that is, the damping device was irreversibly damaged.

The results obtained are summarized in table 1 below.

Table 1

 Sample Number

 Number of impacts Total energy (J) Maximum impact energy (J) Total energy absorbed (J) Energy absorbed (in%)

 S1

 2 0.3 0.3 0.58 90

 S2

 20 1.3 1.3 7.96 50-60

 S3

 8 3.9 3.9 7.15 85-95

 S4

 43 54.66 11.7 54.66 80-90

Thus, each of the samples manufactured according to the present invention has advantageous characteristics with respect to the standard damping devices, in particular sample 1 and, although it is not capable of withstanding higher or prolonged impacts, it has an absorption characteristic of Very favorable energy, situation totally opposite to that of sample 2.

Sample 3 (with shape memory) and sample 4 (superelastic) have excellent characteristics, both of durability and energy absorption, thus providing an additional advantage as damping devices. As already described, sample 3 requires a heating treatment for recovery after each stroke.

Example 2

In this case, sample 4 is compared in a different experiment with a damping device manufactured according to the prior art.

In particular, the comparative structure -C1- is manufactured with the same type of elements of sample 4 (superelastic Nitinol), but the wires that are connecting the support elements are not straight but curved, as shown in Figure 9 , thereby violating the condition of parallelism of the normal planes to the slender metal structure. The comparative example -C1- is representative of the behavior of a damping device such as that described in U.S. Pat. 6,530,564 referred to above.

The sample S4 and -C1- are subjected to a compression test on a Chatillon TCD110 digital force test device that allows the force-stroke curve to be plotted for the entire loading phase.

The results of the tests are shown in Figure 10, in which the reduction in the distance between the two support elements expressed in mm appears on the X axis, and on the Y axis the force expressed in Newton.

The area of the hysteresis cycle represents the energy absorbed by the system, and it is immediately evident that the sample S4 (thicker curve -1001-) has much higher characteristics compared to the comparative example -C1- (curve -1002- ).

In addition, the sample -S4- has another interesting feature, in particular it is characterized by a type of threshold effect, the damping device is very rigid and resistant during the initial compression and then deforms and therefore absorbs energy. This behavior is very different and opposite to that of a current damping device that increases its stiffness and resistance as loads increase and is particularly appreciated in certain applications, for example in transport systems for injured persons, such as extenders or handcarts.

Claims (30)

5 10 fifteen twenty 25 30 35 40 Four. Five fifty 55 60 65 1. Damping device (10; 20; 30; 300; 310; 40; 50; 60; 111) comprising a first support element (11; 31; 41; 51; 61; 1111) and a series of slender metal structures (12, 12 ', 12 ", 12n; 32, 32', 32", 32n, 33; 42, 42 ', 42 ", 42n; 52, 52'; 1112, 1112 ', 1112n, 1113, 1113', 1113n) having a first end and a second end, said slender metal structures having a proportion of slenderness equal to or greater than 10 respectively, in which the slender metal structures are respectively fixed at their first ends to said first support element, in that the slender metal structures are fixed at different points of said support element, characterized in that: - the mutual distance between the slender metal structures of at least one pair of slender metal structures (12, 12 '; 32, 33; 42, 42'; 52; 52 ', 62, 62'; 1112, 1113) is equal to or less than 0.75 times its length -L-, said distance being measured with respect to its first ends, - at least 90% of the planes perpendicular to the adjacent slender structures are mutually parallel or form an angle equal to or less than 20 °, - the slender metal structures are flat or sheet metal elements and / or straight filiform or wire elements, and because the slender metal structures are arranged so that they absorb energy from the impacts acting in a direction perpendicular to the planes that are They are perpendicular to the slender structures. 2. Buffering device according to claim 1, wherein the overall configuration of the device is such that the straight and / or flat slender structures are subjected, in use, to compression loads directed along their axes in the case of filiform or wire elements, or parallel to their planes in the case of sheet or sheet elements. 3. A damping device according to any of the preceding claims, wherein the ratio between the area occupied by the slender metal structures and the overall surface area of the support element to which the slender metal structures are fixed is equal to or greater than 10- 4, preferably equal to or greater than 10-3. 4. Buffering device, according to any of the preceding claims, wherein said length L is between 3 mm and 30 cm. 5. A damping device according to any of the preceding claims, wherein said support element is a flat-shaped element. 6. The damping device according to claim 1, wherein said damping device (60) has a spherical shape and said first support element (61) is a central element thereof. 7. A damping device according to any of the preceding claims, wherein the second ends of said slender metal structures opposed to said first ends are free ends. 8. Damping device (20; 300; 310), according to any one of claims 1 to 6, further comprising a second support element (23; 303; 313; 63) and wherein said second ends of said slender metal structures opposite to their first ends are fixed to said second support element, said slender metal structures respectively being fixed to different points of said second support element. 9. A damping device according to any of the preceding claims, wherein at least 30% and preferably 90% of the slender metal structures are made of a superelastic alloy. 10. A damping device according to any of the preceding claims, wherein at least one of the slender metal structures is made of a shape memory metal. 11. Buffering device according to claim 10, wherein at least 30% of the slender structures are made of a shape memory metal. 12. A damping device according to any one of claims 1 to 9, wherein at least 30% of the slender metal structures are made of a superelastic alloy and at least 30% of the slender metal structure is made of a metal with shape memory. 13. Buffering device according to claim 1, wherein the first ends of the slender metal structures are extended in the support element and locked therein. 5 10 fifteen twenty 25 30 35 40 Four. Five 14. A damping device according to any one of the preceding claims, further comprising one or more elements external to the support element. 15. A damping device according to claim 14, further comprising a series of first support elements arranged in layers one above the other, each of said first support elements being fixed to a series of respective slender metal structures. 16. System, comprising a damping device according to claim 1. 17. System, according to claim 16, wherein the system is a closure system. 18. System, according to claim 16, wherein the system is a part or a component of a support element. 19. System, according to claim 16, wherein the system is a vehicle. 20. System according to claim 19, wherein the damping device is incorporated in a bumper of said vehicle. 21. System, according to claim 19, wherein the damping device is incorporated in a seat belt of said vehicle. 22. System, according to claim 19, wherein the damping device is incorporated in a seat of said vehicle. 23. System, according to claim 16, wherein the system is a transpose system for an injured person. 24. System, according to claim 16, wherein the system is a fabric. 25. System, according to claim 16, wherein the system is a domestic or industrial device. 26. System, according to claim 16, wherein the system is a container. 27. Method for actuating a damping device (1111), according to claim 10, said method comprising a step of supplying a controlled current (I) from a controller (112) to a slender metal structure made of a memory material so, in which the operation of said controller (112) is controlled based on external inputs from one or more sensors. 28. Method according to claim 27, wherein said external inlet is provided by a pressure type sensor (116). 29. The method according to claim 27, wherein said external input is provided by a visual or reconstruction sensor of a scenario (115). 30. The method according to claim 27, wherein said external input is provided by a manually operated sensor (117).